Viessmann VITOPLEX 300 Type TX3A - Extension of the connecting cable; Terminator (2 pce.); 11.8 On site connections; Auxiliary functions for single boiler systems with the Vitotronic 200, type GW1 or Vitotronic 300, type GW2

Extension of the connecting cable
■ Installation spacing 7 to 14 m:
– 2 connecting cables (7.0 m long)
Part no. 7143 495
– 1 LON coupling RJ45
Part no. 7143 496
■ Installation distance 14 to 900 m with plug-in connectors:
– 2 LON plug-in connectors
Part no. 7199 251
– 2-core cable:
CAT5, screened
or
Solid conductor AWG 26-22 / 0.13 mm
2
- 0.32 mm
2
,
Conductor AWG 26-22 / 0.14 mm
2
- 0.36 mm
2
7
4.5 mm - 8 mm
on-site
■ Installation distance 14 to 900 m with junction boxes:
– 2 connecting cables (7.0 m long)
Part no. 7143 495
– 2-core cable:
CAT5, screened
or
Solid conductor AWG 26-22 / 0.13 mm
2
- 0.32 mm
2
,
Conductor AWG 26-22 / 0.14 mm
2
- 0.36 mm
2
7
4.5 mm - 8 mm
on-site
– 2 LON sockets RJ45, CAT6
Part no. 7171 784
Terminator (2 pce.)
Part no. 7143 497
To terminate the LON BUS at the first and last control unit.
11.8 On site connections
Auxiliary functions for single boiler systems with the Vitotronic 200, type GW1 or Vitotronic 300, type GW2
Plug aVD
143
B
A
1 2 3
A
External heating program changeover/mixer "open"
B
External blocking/mixer "close"
A
and
B
are zero volt contacts.
External heating program changeover/mixer open
Closing contact
A
can change the manually selected heating pro-
gram or open the connected mixers.
In coding address "9A", the external function mixer "open" can be allo-
cated to the individual heating circuits.
In coding address "91", the external heating program changeover can
be allocated to the heating circuits.
Operating programs
Symbol Description
9 Central heating OFF and DHW OFF
w Central heating OFF and DHW ON
rw Central heating ON and DHW ON
Subject to the setting of coding address "d5", the system can be
changed from three manually selectable heating programs
9
,
w
,
rw
(contact open) either to
9
or
rw
(contact closed).
External blocking/mixer Close
Closing contact
B
causes the burner to shut down or the mixer to be
closed.
In coding address "99" you select which heating circuits are affected
by the function external blocking or mixer "Close".
Note
The frost protection of the relevant boiler or heating circuit is no longer
effective during the controlled shutdown or with mixer "Close", i.e. the
lower boiler water temperature or flow temperature are no longer
maintained.
Plug
aVH
146
1 2 3
A
External changeover of stepped/modulating burners
B
External demand
A
and
B
are zero volt contacts.
External demand
Closing contact
B
starts the burner of the boiler subject to load.
The boiler water temperature is limited via the maximum set boiler
water temperature or via the mechanical control thermostat.
The set value is selected in coding address "9b".
Control units
(cont.)
70
VIESMANN
OIL/GAS BOILERS
11
5822 426 GB